Extrasolar Planets and Astrobiologyby Caleb Scharf
published by University Science Books, 2008

reviewed by Paul Gilster

Caleb Scharf is director of the Columbia Astrobiology Center. His new book is designed for university courses on the subject, with extensive background not only in the relevant physics and mathematics, but also in chemistry, biology and geophysics, studies the multi-faceted world of astrobiology melds into a complex whole.

The book is actually based on the upper-level course Scharf has been teaching at Columbia. The author tells me in an e-mail that his intent is specifically to reach students serious about moving into the discipline: "The aim is to provide the basis for students to gain a real understanding of how to actually do research on exoplanets, as well as some of the broader science encompassed by astrobiology." Making the point are the exercises designed for each chapter to draw newcomers into research and provide examples for calculation. I also want to mention the book's online component, where news items are cross-referenced with the book.

And I like what planet-hunter Geoff Marcy has to say in his foreword, especially in its hint of long-term interstellar travel:

For the future, NASA and the Jet Propulsion Laboratory have developed the Space Interferometry Mission that will use the interference of light waves gathered by a spaceborne pair of telescopes to detect earth-like planets, and measure their masses, around nearby stars. Just over the horizon are plans for a spaceborne telescope that blocks the glare of nearby stars, allowing us to take images of Earth-like planets and to determine their chemical composition from their spectra. Any worlds having oxygen atmospheres and surface oceans will smell fishy from 40 light years. This census of habitable earths will fill GoogleGalaxy with ports-of-call for our grandchildren who will send robotic probes and later themselves, at least those with extreme daring and patience. The urge to explore these new worlds comes from our anthropological roots at Olduvai Gorge two million years ago. What sets us apart from the stones and the stars is our insatiable desire to understand our kinship with both.

Nicely put, and I especially like that GoogleGalaxy bit, the updated and searchable version of the Encyclopedia Galactica. Scharf looks hard at how we study planet and star formation, how we observe exoplanets and undertake chemical and biological modeling. I'm glad to see that he does not claim definitive status for the book in a field as malleable as this, but treats astrobiology as an 'emerging interdiscipline' - exactly the right phrase - while his audience is "...the student or researcher in astronomy or physics, or possibly someone from the geophysical, chemical, or biological sciences, looking for a deeper understanding of the 'astro' in astrobiology." Those looking for an astrobiology career will want Extrasolar Planets and Astrobiology on their shelves.